The invention relates:to a separating agent metering device for supplying separating agent to the surface of a fuser roller of a printer or copier operating by a transfer-printing method.
A separating agent metering device of the conventional type is disclosed in U.S. Pat. No. 3,964,431. Such a separating agent metering device contains a separating agent feed roller which rolls tangentially against the fuser roller and, during this process, applies liquid separating agent to the surface of the fuser roller.
It has been shown that particularly the separating agent feed roller of a heat-and-pressure fusing device undergoes severe abrasion during operation and therefore has to be exchanged regularly. This frequent exchange is greatly disadvantageous especially since a heat-and-pressure fusing device has an operating temperature of about 200.degree. C. This causes, on the one hand, the high degree of wear and, on the other hand, a long waiting time until the parts to be exchanged have cooled down to the extent that they can be changed. The exchange of the parts is frequently so complicated and time-consuming that additionally a specially trained service engineer has to be called to carry out this work. Experience has further shown that additional costs occur due to the fact that parts to be exchanged are misplaced or damaged by being dropped.
Separating agent feed rollers are usually exchanged completely when their surface has become soiled or damaged. In doing so, valuable parts which are not yet worn, for example heat-resistant bearings which are a constituent part of the separating agent feed roller, are generally also disposed of. The new part to be used is therefore comparatively expensive. The present invention is therefore based on the object of designing the separating agent metering device for supplying separating agent to the surface of a fuser roller of a printer or copier operating by the transfer-printing method in such a way that parts subject to wear can be exchanged in a simple manner, have a long service life, are functionally reliable and cost-effective.